An information recognition apparatus, such as a barcode scanner, for reading a pattern subject to information recognition, such as a one-dimensional code and two-dimensional code (hereinafter referred to as “target pattern”), by means of imaging, and interpreting the information of the read target pattern, has been known heretofore.
It is important for an information recognition apparatus of this kind to image a target pattern adequately, in a state focus is adjusted with respect to a target pattern, in order to interpret the information of the target pattern reliably.
The technology disclosed in patent literature 1, for example, is known as a technique to assist this reading of target pattern information.
In patent literature 1, in order to allow the view at the focal distance to be determined in a convenient fashion and at low cost, guiding light beams are output to a plane where a symbol is formed, so that, when the plane comes to an optimal position to read that symbol, an image is formed in a state in which a prescribed shape is shown on that plane.
Patent Literature
                PTL 1: Published Japanese Translation No. 2009-520249 of the PCT International Publication        